Blading for elastic-fluid turbines.



H.-T. HERB.

BLADING FOR ELASTIC FLUIDTURBINES.

APPLICATION FILED FEB. 24. 1914.

I 1 ,QQ'YAUQ Patented Nov 20, 1917.

IN VE N TOR. /W 7% aw-R AM HIS ATTORNEY IN FACT HERBERT T. HERB; OFPITTSBURGH, PEWEEEVMHA, AdfiIGrNOR T0 WESTINGHUUflE ELECTRIC &MANUFACTURING COMPANY, A. GQRJPOMEION OF PENNSYLVANIA.

BLADING FOR ELASTIC-FLUID TURBINES.

Specification of Letters Patent.

Patented Mandi), di it.

Application filed February 24%, 191a Serial No. 820,586.

To all whom it may concern:

. Be it known that I, HERBERTT. HERB, a citizen of the United States,and a resident of Pittsburgh, in the county of Allegheny and State ofPennsylvania, have made anew and useful Invention in Blading forElastic-Fluid Turbines, of which the fol lowing is a specification.

This invention relates to turbine blading, and more particularly tomeans for securing together the outer ends of blades located in one row.

An object of this'invention is to produce new and improved means forsecuring the outer ends of the blades of a row together for the purposefirst, of forming a shroud or cover for the outer ends of the blades,

and, second, for preventing objectionable vibrations in the blades.

These and other objects I attain in a blade embodying the featuresherein described and illustrated in the single sheet of drawingsaccompanying and forming a part of this application.

In the drawings:

Figure 1 is a fragmental, sectional view of a rotor element of a turbineequipped with a single blade;

Fig. 2 is a fragmental, transverse, sectional view of a blade-mountingelement diagrammatically shown and equipped with blades embodying myinvention;

Fig. 3 is a fragmental, perspective view of a rotor element equippedwith blades embodying my invention;

Fig. 4 is a perspective view blade.

One of the features of my invention is that the separate blades areprovidedwith cover members or spacing pieces which cooperate with eachother when the blades are assembled and form a shroud or cover for theblades of each row.

Another feature of my invention is that the ends of adjacent blades arefirmly secured together so that several blades cooperate with each otherin resisting the v1- bration creating strains to which the blades aresubjected.

In the drawings I have shown a turbine blade-mounting element, which isprovided with overhanging or laterally projecting of a single the outeror free ends of the blades.

flanges 6. Each flange shown is provided with a plurality of radiallyextending blademopntmg slots 7 cut in its lateral face, and asillustrated, each blade 8 is provided with a substantially T-shape shank9 adapted to be lnserted into one of the slots 7 so that its cross bar10 engages the inner face of the flange and thereby holds the blade inplace on the blade-mounting element and prevents it from being thrownoutwardly under the influence of centrifugal or any other displacingforces.

In the drawings the blades illustrated are of the type known as impulseblades, but it will be apparent that my invention may be employed withany kind or type of blades. The body portion of each blade issubstantially crescent shape in cross section; that is, it is providedon one side with a concave working face'll and on the other side with aconvex forward face 12. The outer or free end of each blade is providedwith an integrally formed cover or spacing piece 13, which, asillustrated in the drawings, extends approximately at right an les tothe concave face 11 and overhangs t at face. As illustrated, the coveror spacing piece is rectangular in shape for the purpose of facilitatingthe mounting of blades on the particular blade-mounting elementillustrated. With this construction each blade can be separately slippedinto place on the blade-mounting element by forcing its shank laterallyinto one of the blademounting slots. The slots are so spaced that theforward edge of each spacing piece 13 engages the rear edge of the nextadjacent piece. As illustrated, the pieces 13 are so formed that theforward edge of each of the adjacent piece 13 when the blades areassembled. With this arrangement the spacing pieces cooperate to form acontinuous shroud or cover for each row of blades, and the fluid passagebetween each pair of adjacent blades is closed at each end of the bladeand consequently fluid passing therethrough is prevented from spillingast *or the purpose of preventing the blades from vibrating, I haveprovided new and improved means for securing together the contheseparate blades may be tacting edges of the separate spacin ieces 13 sothat all or a portion of the b a es of one row cooperate in resistingvibrationimparting strains. In my present invention, this isaccomplished by welding or autogenously soldering the contacting edgesof the spacing pieces together.

In carrying out my invention I preferably so form the edges of thespacing pieces 13 that each piece slightly overlaps an adjacent piece inan assembled row of blades. In addition to this I preferably bevel theoverlapping edge of each piece and provide a cooperating beveledshoulder on the overlapped piece so that V-shape and trans verselyextending grooves 14 are formed across the organized or assembled shroudof each row of blades. A separate piece of metal 15 is preferably placedin each of these grooves 14 and the pieces 13 may then be securedtogether by subjecting the'strips 15 to a welding heat and. therebywelding them to each adjacent or contacting piece 13.

It will, of course, be understood that the contacting edges of thespacing pieces 13 may be welded directly together without employing theaccompanying strips 15. This may be accomplished in any suitable manner,such, for example, as by electric welding. After the outer ends of theblades are secured together, the outer face of the shroud may be milledor otherwise trued up if desired.

' It will be understood that the configuration and location of thespacing pieces on materially modified, and that the specific means formounting the blades to the blade-mounting element may be varied, sinceit nor the spacing pieces 16 atthe bases of the blades, are notessential to the invention.

It will also be apparent that other and various changes in detail may bemade without departing from the spirit and scope of the invention as setforth by the appended claims.

Having thus described my invention, what I claim is: l

1. In combination with a turbine, a blade mounting element, and a row of,turbine blades mounted on said element, each blade having an integrallyformed spacing piece at the outer or free end thereof, and a welding tipof reduced section integrally formed alon one edge of each piece.

2.- combination with a turbine, a blade mounting element, and a row ofblades mounted thereon, each blade being provided at its outer end witha substantially rec- 'tangular spacing piece having a welding edge ofreduced section formed on an end thereof and adapted to engage thespacing piece of the next adjacent blade when the blades are assembledin a row,

3. In combination with a blade-mounting element, a row of turbine bladesmounted on said element, each blade having an integrally formed spacingpiece at the outer or free end thereof, said blades being so arrangedthat the spacing pieces of said blades engage each other, and a Weldingstrip for securing each piece to an adjacent piece.

'4. In combination with a turbine, a blade mounting element, a row ofblades mounted on said element, each blade being provided at its outerend with an integrally formed cover portion, an overhan ing welding tip,of reduced vertical thic hness, integrally formed along one edge of eachcover portion, and a tip receiving groove formed along the opposite edgeof each cover portion, said blades being so arranged on the element,that the tip of one cover portion engages and is welded into the grooveof the cover portion of the next adjacent blade.

In testimony whereof, I have hereunto subscribed my name this 19th dayof February, 1914;.

HERBERT T. HERB. Witnesses:

C. W. MoGHnn, E. W. MCCALLISTER.

